Molded composite article and process for producing the same

ABSTRACT

In a molded composite article formed by directly bonding a resin member comprising a polyamide-series resin to a resin member comprising a thermoplastic polyurethane-series resin, the polyamide-series resin comprises a polyamide block copolymer containing (A) a polyether segment having at least one terminal imino group. The polyamide-series resin may comprise a polyamide-series resin having a free amino group in a concentration of not less than about 10 mmol/kg. The molded composite article is producible, for example, by heating at least one of the polyamide-series resin and the thermoplastic polyurethane-series resin to bond the former to the latter. Thus obtained molded composite article is suitable for a member of a shoe and an industrial roll. In such a process, the polyamide-series resin member and the thermoplastic polyurethane-series resin member both of which are different in nature from each other can be directly and firmly bonded together.

TECHNICAL FIELD

The present invention relates to a molded composite article (compositemolded (or shaped) article) in which a resin member comprising aspecific polyamide-series resin is bonded to a resin member comprising athermoplastic polyurethane-series resin in a one-piece constructionwithout an adhesive, and a process for producing the same.

BACKGROUND ART

In order to improve design or decorative property or to impart excellenttouch or texture (e.g., soft texture), there have been proposed thatcomposites (molded composite articles) formed from a combination of aplurality of resins each having a different hardness, for example, amolded composite article in which at least part of a resin moldedarticle is coated with a thermoplastic elastomer. Such a moldedcomposite article is usually produced by adhesion of a plurality ofmolded members through an adhesive. For example, Japanese PatentApplication Laid-Open No. 267585/1996 (JP-8-267585A) (Patent Document 1)discloses a resin molded article in which a plurality of resin moldedarticles formed from a polyamide resin or others are adhered to eachother through a finishing agent such as a urethane polymer or a urethaneadhesive. However, such a process using an adhesive is not onlyuneconomical due to complicated steps, but also has problems such asenvironmental pollution by an organic solvent or others.

On the other hand, from the viewpoint of rationalization of productionprocesses or environmental protection, a process for thermal welding ofa plurality of molded members has been adopted. The molded compositearticle obtained by thermal welding is usually manufactured by a moldingprocess such as a two-color (or double) molding or an insert molding inmany cases. However, combination of different materials subjecting tothermal welding is significantly limited. Moreover, it is not easy toestablish molding conditions to ensure enough bonded strength.

Therefore, in addition to thermal welding, the fused part is reinforcedby a combination use of a process for creating a concavo-convex site (orpart) in the composite area of the molded member to bond mechanically,or a process for coating a primer or others on the bonding (or fusing)part, or other methods. In such a method, however, the molded compositearticle is deteriorated in flexuous property. For example, the hardenedprimer layer easily forms a crack by bending. Moreover, the productionprocess needs to complicate the structure of the molded member,resulting in increase of the number of the production steps.

In order to solve these problems, it has been investigated to use athermoplastic polyurethane as a material for a resin member constitutinga molded composite article. The thermoplastic polyurethane itself isrelatively excellent in adhesiveness. For example, in an application forshoe(s), a molded composite plastic article comprising a polyamide resinand a thermoplastic polyurethane is practically used as a shoe sole. Forexample, Japanese Patent Application Laid-Open No. 505333/1996(JP-8-505333A) (Patent Document 2) discloses that a lightened shoe soleis obtained by inserting or putting a molded article made of athermoplastic resin such as a polyether amide, a polyether ester or apolyurethane in a mold, injection-molding a polyamide elastomercontaining a foaming agent into the mold, and adhering the thermoplasticresin molded article (un-lightweight (un-lightened) plastic) to theelastomer (lightweight thermoplastic elastomer).

In such an application for shoe sole, it is preferred to use a membercomposed of a thermoplastic polyurethane resin excellent in flexibilityin terms of securing flexibility of the whole shoe sole. Moreover, asthe counterpart member of the polyurethane resin, a member composed of apolyamide elastomer excellent in flexibility is frequently selected. Inthe compounding process, both members are generally subjected to thermalwelding in the molding process. In these cases, the polyamide elastomercomposed of a polyamide block copolymer having a polyether segment in amolecule thereof is combined with the thermoplastic polyurethane havinga polyether segment in a molecule thereof. Thereby, affinity betweenpolyether segments in common with both resins is attributed torelatively easy thermal welding therebetween.

However, in this method, water management of the materials in themolding process (usually an injection molding) is difficult, andmoisture absorption of the material significantly decreases the bondedstrength therebetween. Further, the bonded strength is also influencedgreat deal by the temperature of the resin in the molding process. Inthe case of insert-molding either of the members, it is possible thatthe member composed of the polyurethane resin is inserted followed byinjecting the polyamide elastomer thereon (overmolding the polyamideelastomer). However, in the reciprocal case, enough bonded strength isunobtainable. The polyamide elastomer is high in heat resistance and canbe heated up to a sufficiently high temperature (e.g., 250° C.) in theinjection molding, but the polyurethane can be heated only up to about200° C. because of poor heat resistance thereof. The reason is that themelting point of the polyamide elastomer is generally higher than thatof the polyurethane elastomer. Accordingly, the above combination hadthe problem that economically disadvantageous multi-color moldingmachine was forced to be employed.

Further, as mentioned above, since the bonding of this combinationdepends on affinity between polyether segments in common with bothresins, it is drastically difficult to combine a polyurethane having asmall content of the polyether segment, particularly a costlyadvantageous polyester-series polyurethane, with a polyamide elastomer,and therefore commercially disadvantageous factors have been severelyleft.

-   -   Patent Document 1: JP-8-267585A    -   Patent Document 2: JP-8-505333A

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

It is therefore an object of the present invention to provide a moldedcomposite article in which a resin member comprising an extensivethermoplastic polyurethane-series resin is directly and firmly bonded toa resin member comprising a flexible polyamide-series resin without anadhesive.

It is another object of the present invention to provide a process forproducing a molded composite article in which a resin member comprisinga flexible polyamide-series resin and a resin member comprising athermoplastic polyurethane-series resin are firmly bonded together bythermal welding in the most rational (economical) manner without goingthrough complicated production steps.

Means to Solve the Problem

The inventors of the present invention made intensive studies to achievethe above objects and finally found that use of a polyamide-series resinwhich comprises as a main component a polyamide block copolymer having aspecific polyether segment realizes high and stable bonded strengthbetween the polyamide-series resin and a wide range ofpolyurethane-series materials, and that a molded composite article beinguseful for a shoe member, a roller for industrial instruments, or othermembers is commercially advantageously producible in a rational andeconomical process. The present invention was accomplished based on theabove findings.

That is, the molded composite article of the present invention is amolded composite article which comprises (Ia) a resin member comprisinga polyamide-series resin and (IIa) a resin member which is directlybonded (joined) to the resin member (Ia) and comprises a thermoplasticpolyurethane-series resin, wherein the polyamide-series resin comprisesa polyamide block copolymer containing (A) a polyether segment having atleast one terminal imino group (or having an imino group at least at oneterminal (end)) The polyamide block copolymer may comprise a polyamideelastomer. Moreover, the polyether segment (A) maybe, for example, apolyether segment is a polyether segment which is a condensate(condensation product) of a polyhydric alcohol having 2 to 8 carbonatoms (preferably a straight or branched chain aliphatic polyhydricalcohol having 2 to 4 carbon atoms, and more preferably a straight orbranched chain aliphatic polyhydric alcohol having 2 to 3 carbon atoms),and has at least one terminal imino group. Moreover, the polyethersegment (A) may have a branched chain having a free amino group. Theproportion of the polyether segment (A) may be, for example, in thepolyamide block copolymer (the polyamide entirety), about 10 to 90% byweight (preferably about 20 to 80% by weight, and more preferably about25 to 70% by weight). Further, the polyamide-series resin may have afree amino group in a concentration of not less than about 10 mmol/kg,preferably not less than about 20 mmol/kg, more preferably not less thanabout 30 mmol/kg (e.g., about 45 mmol/kg), or may be a resin compositionwhich comprises a polyamide block copolymer containing the polyethersegment (A). Such a polyamide-series resin composition may be, forexample, a resin composition which comprises both the polyamide blockcopolymer containing the polyether segment (A) and (C) a compound havinga free amino group. The compound (C) having a free amino group maycomprise at least one member selected from the group consisting of amonoamine, a polyamine, a polyamide oligomer and a polyamide-seriesresin. Moreover, the proportion of the compound (C) having a free aminogroup may be, in the total resin composition, for example, about 0.01 to20% by weight, preferably about 0.1 to 15% by weight, and morepreferably about 0.5 to 10% by weight (e.g., about 1 to 8% by weight).

The thermoplastic polyurethane-series resin may usually comprise athermoplastic polyurethane elastomer. Moreover, the thermoplasticpolyurethane-series resin may comprise a polyester polyurethaneobtainable from a polyester diol. Such a thermoplasticpolyurethane-series resin may comprise, for example, at least one memberselected from the group consisting of a polyether urethane elastomer, apolyester ether urethane elastomer, and a polycarbonate urethaneelastomer. The molded composite article of the present invention isuseful for a variety of members, for example, may be a member of a shoeor a roll.

The molded composite article may be produced, for example, by heating atleast one selected from the group consisting of (i) the polyamide-seriesresin or a resin member thereof (Ia) and (ii) the thermoplasticpolyurethane-series resin or a resin member thereof (IIa) to bond theformer (i) to the latter (ii). More specifically, the process maycomprise (a) heating the thermoplastic polyurethane-series resin to bemolten (fused or melted) with bringing the thermoplasticpolyurethane-series resin in the molten state into contact with at leastpart of a resin member comprising the polyamide-series resin to bondboth resins together, (b) heating the polyamide-series resin to bemolten with bringing the polyamide-series resin in the molten (fused ormelted) state into contact with at least part of a resin membercomprising the thermoplastic polyurethane-series resin to bond thepolyamide-series resin to the thermoplastic polyurethane resin member,or (c) heating both of the polyamide-series resin and the thermoplasticpolyurethane-series resin to be molten with bringing thepolyamide-series resin in the molten state into contact with thethermoplastic polyurethane-series resin in the molten state to bond bothresins together. Further, the polyamide-series resin and thethermoplastic polyurethane-series resin may be bonded together in themolding process by a molding method selected from the group consistingof a heat press molding, a vacuum molding, an injection molding, anextrusion molding, and a blow molding.

Incidentally, throughout this specification, the meaning of the term“resin” includes “a resin composition”. Moreover, throughout thisspecification, the term “adhesion (or adhering)” means a technique forcompounding a plurality of members through an adhesive, the term“bonding (or joining)” means a technique for compounding a plurality ofmembers without an adhesive, and the both terms are distinguished fromeach other. Welding (or thermal welding or fusing) is one embodiment ofbonding.

Effects of the Invention

According to the present invention, since a specific polyamide-seriesresin is combined with a thermoplastic polyurethane-series resin, aresin member comprising an extensive thermoplastic polyurethane-seriesresin is directly and firmly can be bonded or joined to a resin membercomprising a flexible polyamide-series resin without an adhesive.Therefore, even if using members which are different in characteristicsfrom each other, i.e., the resin member comprising a polyamide-seriesresin and the resin member comprising a thermoplasticpolyurethane-series resin, these resin members are directly and firmlybondable or joinable together without an adhesive. Moreover, in a mostrational (economical) manner without going through complicatedproduction steps, a molded composite article is producible in which aresin member comprising a flexible polyamide-series resin and a resinmember comprising a thermoplastic polyurethane-series resin are firmlythermal-welded together.

DETAILED DESCRIPTION OF THE INVENTION

The molded composite article of the present invention comprises (Ia) aresin member comprising a polyamide-series resin and (IIa) a resinmember which is directly bonded to the resin member (Ia) and comprises athermoplastic polyurethane-series resin.

(Polyamide-series Resin)

The polyamide-series resin used in the present invention comprises apolyamide block copolymer which comprises a polyamide-block copolymercontaining (A) a polyether segment having at least one terminal iminogroup (or has an imino group at least at one terminal) (e.g., at bothterminals, at least two terminals, hereinafter, sometimes inclusivelyreferred to as both terminals). Hereinafter such a polyamide blockcopolymer containing the polyether segment (A) is sometimes referred toas simply a polyamide block copolymer, or a polyamide block copolymerhaving an imino group. The polyamide block copolymer (including apolyamide block copolymer having an imino group) may be usually apolyamide elastomer. More specifically, the polyamide copolymer maycomprise a polyamide elastomer which comprises (B) a polyamide chain asa hard segment, and a polyether chain (the polyether segment (A)) as asoft segment. Incidentally, in the present description, the term “block”means a block or segment containing a repeating unit, and is notnecessary to be a block having a long repeating unit.

The polyamide chain (B) constituting a hard block (a hard segment) ofthe polyamide block copolymer (a polyamide block copolymer having animino group) may comprise a monomer arrangement similar to anarrangement of a conventional polyamide-series resin (or a polyamide, apolyamide unit, a polyamide segment), for example, an aliphaticpolyamide-series resin (an aliphatic polyamide), an alicyclicpolyamide-series resin (an alicyclic polyamide), an aromaticpolyamide-series resin (an aromatic polyamide), and other polyamides.Such a polyamide chain (B) (a hard segment) may be a homopolyamide or acopolyamide.

Among the hard segments comprising the aliphatic polyamide, thehomopolyamide segment may include a condensate (condensation product) ofan aliphatic diamine component [e.g., a C₄₋₁₆alkylenediamine such astetramethylenediamine, hexamethylenediamine or dodecanediamine(preferably a C₄₋₁₄alkylenediamine, particularly aC₆₋₁₂alkylenediamine)] and an aliphatic dicarboxylic acid component[e.g., an alkanedicarboxylic acid having about 4 to 20 carbon atoms,such as adipic acid, sebacic acid, or dodecanedioic acid (preferably aC₄₋₁₆alkanedicarboxylic acid, and particularly a C₆₋₁₄alkanedicarboxylicacid)], for example, a polyamide 46, a polyamide 66, a polyamide 610, apolyamide 612, and a polyamide 1010;a homopolyamide of a lactam [e.g., alactam having about 4 to 20 (preferably about 4 to 16) carbon atoms,such as ε-caprolactam or ω-laurolactam] or an aminocarboxylic acid[e.g., an aminocarboxylic acid having about 4 to 20 (preferably about 4to 16) carbon atoms, such as ω-aminoundecanoic acid], for example, apolyamide 6, a polyamide 11, and a polyamide 12;and others.

Moreover, the copolyamide segment may include a copolyamide which is acopolymer of constitutive components of the homopolyamide segment (e.g.,the aliphatic diamine components, the aliphatic dicarboxylic acidcomponents, the lactams and the aminocarboxylic acids). Examples of thecopolyamide may include a copolymer of 6-aminocaproic acid and12-aminododecanoic acid; a copolymer of 6-aminocaproic acid,12-aminododecanoic acid, hexamethylenediamine and adipic acid; acopolymer of hexamethylenediamine, adipic acid, hydrogenated dimer acidand 12-aminododecanoic acid; a polyamide 6/11; a polyamide 6/12; apolyamide 66/11; a polyamide 66/12; and others.

The hard segment comprising the alicyclic polyamide may include ahomopolyamide or copolyamide having at least one component selected fromthe group consisting of at least an alicyclic diamine and an alicyclicdicarboxylic acid as a constitutive component. For example, there may bementioned an alicyclic polyamide obtained from an alicyclic diamineand/or an alicyclic dicarboxylic acid as at least part of one componentamong a diamine component and a dicarboxylic acid component eachconstituting the polyamide. As the diamine component and thedicarboxylic acid component, the above-mentioned aliphatic diamine(s)and/or aliphatic dicarboxylic acid(s) are preferably used in combinationwith the above-mentioned alicyclic diamine(s) and/or alicyclicdicarboxylic acid(s). Such a resin comprising the alicyclic polyamidegenerally has high transparency, and is known as a so-called transparentpolyamide. Examples of the alicyclic diamine may include adiaminocycloalkane such as diaminocyclohexane (e.g., adiaminoC₅₋₁₀cycloalkane); a bis(aminocycloalkyl)alkane such asbis(4-aminocyclohexyl)methane, bis(4-amino-3-methylcyclohexyl)methane or2,2-bis(4′-aminocyclohexyl)propane [e.g., abis(aminoC₅₋₈cycloalkyl)C₁₋₃alkane]; and others. Moreover, the alicyclicdicarboxylic acid may include a cycloalkanedicarboxylic acid such ascyclohexane-1,4-dicarboxylic acid or cyclohexane-1,3-dicarboxylic acid(for example, a C₅₋₁₀cycloalkane-dicarboxylic acid) and others.

The aromatic polyamide-series segment may include a polyamide in whichat least one component of the diamine component (e.g., an aliphaticdiamine component) and the dicarboxylic acid component (e.g., analiphatic dicarboxylic acid component) comprises an aromatic component,for example, a polyamide having an aromatic component in part or wholeof the diamine component(s) [for example, a condensation product of anaromatic diamine (e.g., metaxylylenediamine) and an aliphaticdicarboxylic acid, such as MXD-6], a polyamide having an aromaticcomponent in part or whole of the dicarboxylic acid component [e.g., acondensation product of an aliphatic diamine (e.g.,trimethylhexamethylenediamine) and an aromatic dicarboxylic acid (e.g.,terephthalic acid, isophthalic acid)], and others.

The polyamide segment (a hard segment) may further include a polyamidein which a dimeric acid is used as the dicarboxylic acid component, apolyamide in which a branched chain structure is introduced by using asmall amount of a polyfunctional polyamine and/or polycarboxylic acidcomponent, a modified polyamide (e.g., an N-alkoxymethylpolyamide), apolyamide block copolymer, and other polyamides.

The polyamide segment (a hard segment) may comprise a hard segment(s)singly or in combination of not less than two species.

Among a variety of polyamides exemplified above, as a polyamide moresuitably adaptable as a polyamide chain (B) constituting the hardsegment of the polyamide block copolymer (a polyamide copolymer havingan imino group), there may be exemplified an aliphatic polyamide (ahomopolyamide, a copolyamide), and the like. The monomer of thepolyamide (e.g., a diamine, a dicarboxylic acid, and an aminocarboxylicacid) may have carbon atoms in the range of about 6 to 12.

The polyether segment (A) is usually a polyether segment which is acondensate (condensation product) of a polyhydric alcohol (e.g., a diolsuch as an aliphatic diol) and has at least one terminal imino group.More specifically, “(A) a polyether segment having imino groups at bothterminals” constituting the soft block (soft segment) of the polyamideblock copolymer employs, as a precursor, a condensation product(condensate) of a polyhydric alcohol having at least one terminal aminogroup (e.g., at both terminals, and at least two terminals), that is, apolyether (e.g., an aliphatic homopolyether, an aliphatic copolyether,or a mixture thereof) having at least one terminal amino group (e.g.,both terminals). More specifically, the polyamide block copolymer may beobtained by a condensation (copolymerization or copolycondensation) ofthe hard segment [or a constitutive component thereof (e.g., a diaminecomponent, a dicarboxylic acid component, a lactam or an aminocarboxylicacid)] with a polyether having at least one terminal amino group (or twoterminals) (or a polyether component, hereinafter sometimes referred toas simply a polyether). For example, the polyamide block copolymer maybe (i) a block copolymer obtained by a condensation of a hard segmenthaving a carboxyl group at terminal(s) (e.g., an aliphatic polyamidehaving at least one terminal carboxyl group) with a polyether component,or (ii) a block copolymer obtained by a condensation(copolycondensation) of a polyether component and a constitutivecomponent of the hard segment [e.g., a component containing adicarboxylic acid component (e.g., at least one member selected from thegroup consisting of an aliphatic dicarboxylic acid, an alicyclicdicarboxylic acid and an aromatic dicarboxylic acid, particularly analiphatic dicarboxylic acid) and a diamine component (e.g., at least onemember selected from the group consisting of an aliphatic diamine, analicyclic diamine and an aromatic diamine), a lactam, or anaminocarboxylic acid].

As a polyether constituting the polyether segment (A), or a precursor ofthe polyether segment (A), there may be mentioned an aliphaticpolyether, an alicyclic polyether, an aromatic polyether, and others.The polyethers may be used singly or in combination.

As the aliphatic polyether, there may be mentioned an aliphaticpolyether or an aliphatic poly(oxy)alkylene glycol) which is acondensation product of a polyhydric alcohol such as an aliphaticpolyhydric alcohol (an aliphatic diol) [e.g., an aliphatic diol (diolcomponent) having about 2 to 18 carbon atoms, for example, a straightchain aliphatic diol (e.g., ethylene glycol, trimethylene glycol, andtetramethylene glycol), and a branched aliphatic diol (e.g., propyleneglycol, 2-methyl-1,3-propanediol, 3-methyl-1,5-pentanediol,2-methyl-1,8-octanediol, 2,2-diethyl-1,3-propanediol, and1,9-nonanediol)], and others. Moreover, the aliphatic polyether may be acopolyether, and such an aliphatic copolyether may include acondensation product (copolycondensation product or copolymer, that is,an aliphatic copolyether) of different species of aliphatic diols amongthese aliphatic diols, in addition, a condensation product(copolycondensation product or copolymer) of the aliphatic diol with theafter-mentioned alicyclic or aromatic diol, a condensation product(copolycondensation product or copolymer) of the aliphatic diol with apolyhydric alcohol, and others. Such a polyhydric alcohol may include apolyol such as the above-exemplified polyhydric alcohols for thehomopolyether (e.g., diethylene glycol, a polyethylene glycol, and apolypropylene glycol), further, a polyhydric alcohol being tri- topolyfunctional (e.g., about tri- to octafunctional, preferably abouttri- to hexafunctional) or a condensation product thereof [e.g., analkanepolyol (e.g., a C₃₋₈alkanetriol such as glycerin,trimethylolethane, or trimethylolpropane, a C₄₋₁₀alkanetetraol such aspentaerythritol), a condensation product of an alkanepolyol (e.g.,diglycerin, ditrimethylolpropane, dipentaerythritol, and polyglycerin)],and others. These polyhydric alcohols may be used singly or incombination.

Among the aliphatic polyethers, in the present invention, from theviewpoint of achievement in higher bonded strength of the moldedcomposite article, the preferred (advantageous) aliphatic polyetherincludes a condensation product of a straight or branched chainaliphatic polyhydric alcohol having not more than 8 carbon atoms (e.g.,2 to 8 carbon atoms), preferably not more than 4 carbon atoms (e.g., 2to 4 carbon atoms), more preferably not more than 3 carbon atoms (e.g.,2 to 3 carbon atoms) (and, if necessary, further a polyhydric alcoholbeing tri- to polyfunctional, or a condensation product thereof).

As the alicyclic polyether, there may be mentioned an alicyclichomopolyether such as a condensation product of an alicyclic polyhydricalcohol (e.g., a C₅₋₁₀cycloalkanediol such as cyclohexanediol orcyclohexane dimethanol, preferably a C₅₋₈cycloalkanediol); an alicycliccopolyether such as a condensation product (a copolycondensation productor a copolymer) of the above-mentioned alicyclic polyhydric alcohol witha copolycondensation component (e.g., an alicyclic diol different fromthe alicyclic polyhydric alcohol, and the above-mentioned polyhydricalcohol being tri- to polyfunctional); and others. Moreover, as thearomatic polyether, there may be mentioned an aromatic homopolyethersuch as a condensation product of an aromatic polyhydric alcohol [e.g.,a dihydroxyarene which may have a substituent (e.g., adihydroxyC₆₋₁₂arene such as a dihydroxybenzene, a dihydroxytoluene, or adihydroxybiphenyl), a bisarylalkane which may have a substituent (e.g.,a bis(hydroxyC₆₋₁₀aryl) straight or branched chain C₁₋₄alkane such asbisphenol A)], an aromatic copolyether such as a condensation product (acopolycondensation product or a copolymer) of the above-mentionedaromatic polyhydric alcohol with a copolycondensation component (e.g.,an aromatic diol different from the aromatic polyhydric alcohol, and theabove-mentioned polyhydric alcohol being tri- to polyfunctional), andothers. Incidentally, the alicyclic polyhydric alcohol (or the alicyclicpolyether) or the aromatic polyhydric alcohol (or the aromaticpolyether) each having amino groups at both terminals may be an aimedcomponent in the present invention. However, these compounds aredifficult in synthesis, in addition, these compounds deteriorates inflexibility. Therefore, these compounds are practically used as acopolymerization component with the aliphatic polyhydric alcohol (thatis, a copolycondensation component of the aliphatic polyether).

The polyamide block copolymer employed in the present inventionessentially has the polyether segment (A) having at least one terminalimino group (having an imino group at least at one terminal) (e.g., bothterminals (ends)). Therefore, the above various species of polyethersforming a polyether chain need to have an amino group at terminal(s) ofa molecule thereof upon using the polyethers as a polyether chain (forproducing the polyamide block copolymer). More specifically, thepolyamide block copolymer is obtained by a polycondensation (orcopolycondensation) of a polyamide component corresponding to at leastthe polyamide chain (B) (more concretely, a polyamide component having acarboxyl group at terminal (s)) with a polyether having at least oneterminal amino group (i.e., a polyether polyamine) corresponding to thepolyether segment (A) (or a polyether chain), and if necessary, othercomponents, for example, a polyether free from an amino group. That is,the polyether segment (A) is a segment containing a polyether unit andan imino group constituting at least one amide bond adjacent to thepolyether unit (or an imino group adjacent to the carbonyl group). Forexample, the polyether segment (A) may be (i) a segment containing apolyether unit and two imino groups which are situated (located) at bothterminals of the polyether unit and constitute amide bonds, or may be(ii) a segment containing a polyether unit, an imino group which issituated at one terminal of the polyether unit and constitutes an amidebond, and an amino group which is situated at the other terminal of thepolyether unit.

Such a polyether having an amino group(s) (a precursor of the polyethersegment (A)) may also include a polyether polyamine having at least oneterminal amino group (e.g., both terminals, and at least two terminals)of the polyether such as the aliphatic polyether, for example apolyoxyalkylenepolyamine, in addition, an oligomer of such a polyetherhaving an amino group(s) (a polyether-polyamine). Moreover, in the casewhere the polyether having an amino group(s) has a branched chain (orside chain, or side chain in the polyamide copolymer), the branchedchain may have an amino group. That is, the polyether segment (A) may bea polyether segment which has a branched chain having a free aminogroup.

As the typical polyether-polyamine, there may be exemplified analiphatic polyether (polyoxyalkylenepolyamine) having an amino group atterminal(s) (or both terminals, two terminals) represented by thefollowing formula (1), an aliphatic polyether (polyoxyalkylenepolyamine)having at least three terminal amino groups (i.e., two terminals (bothterminals) of the main chain and terminal(s) of the side chain)represented by the following formula (2), and others.H₂N—[R¹—(O—R²)_(m)—OR³—NH]_(n)—H   (1)A-[(O—R⁴)_(p)—NH₂]_(q)   (2)

In the formula, R¹ to R⁴ are the same or different, and each representan alkylene group, A represents an alkane skeleton, m, n and p denote aninteger of not less than 1, q denotes an integer of not less than 3.

In the above formula (1) or (2), the alkylene groups represented by thegroups R¹ to R⁴ are not limited to a specific one, and may be the sameor different, for example, may be a C₂₋₄alkylene group (e.g., ethylenegroup, trimethylene group, propylene group, or butane-1,2-diyl group).In particular, a C₂₋₃alkylene group (particularly ethylene group orpropylene group) is preferred. Incidentally, in the case where m, n, pand q are an integer of not less than 2, each of the alkylene groups R¹to R⁴ may be the same or different from each other. For example, in thecase where m is an integer of not less than 2, the polyoxyalkylene unitmay comprise different species of alkyleneoxy groups (e.g., combinationof ethyleneoxy group and propyleneoxy group).

Moreover, examples of the alkane skeleton represented by A may includean alkane skeleton corresponding to a polyhydric alcohol being tri- topolyfunctional, for example, an alkane corresponding to the polyhydricalcohol being tri- to polyfunctional (e.g., a C₃₋₈alkane such aspropane, 2,2-dimethylpropane or 2,2-dimethylbutane) or a(poly)alkoxyalkane corresponding to a condensation product of thepolyhydric alcohol being tri- to polyfunctional (e.g., dipropyl ether,and di(2,2-dimethylbutyl)ether), and others.

Each of m and p may sufficiently be an integer of not less than 1 (e.g.,about 1 to 200), and may be preferably about 1 to 100, and morepreferably about 1 to 80. Moreover, n may sufficiently be an integer ofnot less than 1 (e.g., about 1 to 20), and may be preferably about 1 to10, and more preferably about 1 to 6 (particularly, about 1 to 4).Moreover, q may sufficiently be an integer of not less than 3, and maybe, depending on the number of functional groups (the number of hydroxylgroups) of a polyhydric alcohol being tri- to polyfunctional (or havingnot less than three functional (hydroxyl) groups) or a condensationproduct thereof, for example, about 3 to 10, preferably about 3 to 8,and more preferably about 3 to 6.

Such a polyether having amino groups may include, for example, apolyether available as a series of polyethers called as JEFFAMINE(registered trade mark) supplied from Huntsman Corp., Suntechno ChemicalCo. and the like (e.g., JEFFAMINE “XTJ-500”, “XTJ-502”, “ED-600”,“ED-2003”, “EDR-148”, “XTJ-504”, “D-230”, “D-400”, “D-2000”, “XTJ-510”,“D-4000”, “XTJ-511”, “XTJ-512”, “T-403”, “XTJ-509”, “XTJ-542”, “T-3000”,and “T-5000”), and others, and undoubtedly, the polyether having aminogroups is not limited to the above polyethers.

The polyethers having amino groups may be used singly or in combination(in a mixture thereof). In particular, in the case where a main chain ofthe polyether contains a lot of polyglycol units (e.g., apoly(oxy)alkylene glycol unit) having high water-absorbability, forexample, in the case where the main chain contains ethylene glycol unitsor the like, a polyamide block copolymer containing the above polyglycolunits has an extremely high water-absorbability and water-emissivity.Moreover, these polyamide block copolymers often generate a phenomenon,so-called “blooming” under high humidity. However, such a phenomenondoes not occur in the case of subjecting a molded material to a thermalhistory once at a predetermined temperature [for example, not lower than80° C. (e.g., about 80 to 150° C.)]. This thermal history may beindependently carried out. Moreover, in the case where the heat uponproducing the composite of the polyamide block copolymer with thepolyurethane-series resin satisfies the above temperature condition ofthe thermal history, in the event, the blooming phenomenon can beinhibited by the process for producing the composite.

Incidentally, in the polyamide copolymer (polyamide copolymer having animino group), the proportion of the polyether segment (A) may be, in thepolyamide block copolymer, about 3 to 95% by weight (e.g., about 10 to90% by weight), preferably about 5 to 85% by weight (e.g., about 20 to80% by weight), and more preferably about 8 to 75% by weight (e.g.,about 25 to 70% by weight).

As described above, the polyamide block copolymer according to thepresent invention comprises the polyether segment (A) having an iminogroup at terminal(s) (or both terminals) as an essential constitutivecomponent. However, the above description undoubtedly does not mean thatall of the polyether components (polyether segments) being one of theconstitutive components of the polyamide block copolymer are thepolyether segment (A) having an imino group(s) (at both terminals). Thatis, the polyether segment constituting the polyamide block copolymer maysingly comprise the polyether segment (A) having an imino group(s) atboth terminals, or may comprise the polyether segment (A) having iminogroups at both terminals and another polyether segment (e.g., apolyether segment free from imino groups at both terminals). In theconcrete embodiment of the latter, part of the polyether segment (softsegment) constituting the polyamide block copolymer may be a polyethersegment other than the polyether segment (A) (e.g., a polyether segment(A′) free from imino groups at both terminals) in a range (proportion)of, for example, up to 50% by mole (e.g., about 1 to 40% by mole) in thewhole polyether segment, preferably up to 30% by mole (e.g., about 3 to25% by mole), and more preferably up to 20% by mole (e.g., about 5to20%by mole). As a precursor of such polymer segments other than thepolyether segment (A), there may be exemplified a polyether segment (A′)free from imino groups at both terminals, such as the above illustratedpolyether (e.g., an aliphatic polyether), more specifically, a polyetherhaving at least one terminal hydroxyl group (e.g., both terminals).

In the present invention, a polyether segment (A) having an imino groupat terminal(s) (both terminals) binds to a polyamide segment (B) byamide bond to form the polyamide block copolymer. That is, the polyamideblock copolymer is obtainable by a condensation (dehydrationcondensation, polycondensation) of a polyamide (or a constitutivecomponent thereof) as the precursor of the polyamide segment (B) and anpolyether (polyether polyamine) as the precursor of the polyethersegment (A) having an imino group(s) at both terminals, and ifnecessary, other component(s) (e.g., the above-mentioned polyetherhaving at least one terminal hydroxyl group). The polyamide as theprecursor of the polyamide segment (B) includes a polyamide (or aconstitutive component thereof, for example, a diamine component and adicarboxylic acid component, a lactam or aminocarboxylic acid component)having at least one terminal carboxyl group (e.g., at both terminals, atleast two terminals), and the polyether as the precursor of thepolyether segment (A) includes a polyether (polyether polyamine) havingat least one terminal amino groups (e.g., at both terminals).Incidentally, in the case of using the polyether segment (A′) free fromimino groups at both terminals as a constitutive component of thepolyether segment, the polyether segment (A′) practically binds with thepolyamide segment (B) by an ester bond.

In the case where the polyether segment (A) having imino groups at bothterminals or the polyether segment (A′) free from an imino group atterminal(s) (both terminals) is connected to a polyamide segment (B),the polyamide as the precursor may have carboxyl groups at bothterminals. In such a case, if necessary, an additional dicarboxylicacid(s) may be used. Examples of the suitable dicarboxylic acid mayinclude the above-illustrated dicarboxylic acids, for example, analiphatic dicarboxylic acid having about 4 to 20 carbon atoms, andpreferably about 6 to 12 carbon atoms (e.g., adipic acid, sebacic acid,and dodecanedioic acid).

The molecular weight (or number average molecular weight) of thepolyether having an amino group (or one unit of the polyether segment(A)) may be, for example, about 100 to 20000, preferably about 120 to10000, and more preferably about 130 to 8000, and more preferably about140 to 6000 (e.g., about 145 to 5000). In particular, the number averagemolecular weight of the polyether (e.g., the polyether polyamine) havingan amino group at terminal(s) (or both terminals), which is a precursorof the polyether segment (A) having an imino group at terminal(s) (orboth terminals) for producing the polyamide block copolymer may be, forexample, about 100 to 5000 g/mole, preferably about 300 to 3000 g/mole,and more preferably about 500 to 2000 g/mole. The same is applied to thenumber average molecular weight of the polyether corresponding to thepolyether segment (A′) free from an imino group at terminal(s) (or bothterminals).

Moreover, the number average molecular weight of the polyamide blockcopolymer (the polyamide block copolymer having an imino group) may be,for example, about 6000 to 100000, preferably about 8000 to 50000, andmore preferably about 10000 to 30000.

A variety of polyamide block copolymers are presumable depending on thespecies of the polyamide segment (B), polyether segment (A) having animino group at terminal(s) (or both terminals), and polyether segment(A′) free from imino groups at both terminals, and according to each ofthe molecular weight, composition ratio, and further monomer formulationof each of the segments. Such a polyamide block copolymers (polyamideblock copolymers having an imino group) may be used singly or incombination.

Incidentally, in the molded composite article of the present invention,the polyamide-series resin may sufficiently comprise at least thepolyamide block copolymer (a polyamide block copolymer having an iminogroup). The polyamide-series resin may comprise such a polyamide blockcopolymer having an imino group(s) alone, or further comprise apolyamide-series resin (sometimes referred to as additional (another)polyamide-series resin) which is out of the category of the abovepolyamide block copolymer. For example, the polyamide-series resin inthe present invention may be a blend or alloy of the polyamide blockcopolymer (i.e., the polyamide block copolymer having an imino group)which contains the polyether segment (A) having an imino group(s) atterminal(s) (or both terminals) as the essential constitutive component,and the additional polyamide-series resin. The preferred additionalpolyamide-series resin includes, for example, a polyamide blockcopolymer (e.g., a polyamide block copolymer which has no polyethersegment (A) having imino groups at both terminals) which is out of thecategory of the polyamide block copolymer (the polyamide block copolymerhaving an imino group(s)), an aliphatic polyamide-series resin (e.g.,the above-exemplified aliphatic polyamide-series resins), an alicyclicpolyamide-series resin (e.g., the above-exemplified alicyclicpolyamide-series resins), an aromatic polyamide resin (e.g., theabove-exemplified aromatic polyamide-series resins), and others. It issuggested that the proportion of the polyamide block copolymer which hasthe polyether segment (A) having an imino group(s) at terminal(s) (orboth terminals) as the essential component (the proportion of thepolyamide block copolymer having an imino group) is, based on the weightratio, not less than 50% (e.g., 55 to 99%), preferably not less than 60%(e.g., 65 to 95%), and more preferably not less than 70% (e.g., 70 to90%) relative to the whole blend or alloy.

As the polyamide block copolymer completely free from the polyethersegment (A) having an imino group(s) at terminal(s) (or both terminals),there may be mentioned a polyamide-polyether block copolymer, apolyamide-polyester block copolymer, a polyamide-polycarbonate blockcopolymer, and others.

In these block copolymers, the block component contained in a moleculethereof may include a diol component such as an aliphatic diol [e.g., analiphatic diol having about 2 to 12 carbon atoms, for example, astraight chain aliphatic diol (e.g., ethylene glycol, propylene glycol,and tetramethylene glycol), and a branched aliphatic diol (e.g.,2-methyl-1,3-propanediol, 3-methyl-1,5-pentanediol,2-methy-1,8-octanediol, 2,2-diethyl-1,3-propanediol, and1,9-nonanediol)], an alicyclic diol, or an aromatic diol [e.g., adihydroxyarene which may have a substituent (e.g., a dihydroxyC₆₋₁₂arenesuch as dihydroxybenzene, dihydroxytoluene, or dihydroxybiphenyl), and abisarylalkane which may have a substituent (e.g., abis(hydroxyC₆₋₁₀aryl) straight or branched C₁₋₄alkane such as bisphenolA)], and/or a dicarboxylic acid component such as an aliphaticdicarboxylic acid (e.g., an alkane dicarboxylic acid having about 4 to20 carbon atoms such as adipic acid, sebacic acid or dodecanedioicacid), an alicyclic dicarboxylic acid (e.g., a cycloalkane dicarboxylicacid having 5 to 10 carbon atoms such as cyclohexane-1,4-dicarboxylicacid or cyclohexane-1,3-dicarboxylic acid), and an aromatic dicarboxylicacid (e.g., terephthalic acid, and isophthalic acid), and others.

For example, the polyamide-ether block copolymer is, a polyamidecopolymer having in a molecule thereof a polyether comprising at leastone member selected from the above-mentioned diol components as one ofthe blocks or segments. Moreover, the polyamide-polyester blockcopolymer is a polyamide copolymer having in a molecule thereof apolyester as one of the blocks or segments, where the polyester isobtained by polycondensation of at least one member selected from thediol components and at least one member selected from the dicarboxylicacid components. The polycarbonate-polyamide block copolymer is apolyamide copolymer having in a molecule thereof a polycarbonate esterof at least one diol selected from the diol components as one of theblocks or segments.

In the polyamide block copolymer, a polyether block, a polyester blockand a polycarbonate block which are contained in the copolymer are oftenused for the purpose of imparting softness or flexibility to thepolyamide (as a soft block). A polyamide block copolymer having bothsuch a soft block (or soft segment) and a polyamide block (hard block orhard segment) is referred to as a polyamide elastomer.

The polyamide block copolymer is obtained by copolycondensation of apolyamide block having a reactive terminal group, and any one of apolyether block, a polyester block and a polycarbonate block each havinga reactive terminal group, or a combination thereof. For example, apolyether ester amide-series block copolymer (polyether polyamide blockcopolymer) is obtained by a copolycondensation of a polyamide blockhaving an amino group as the terminal group and a polyoxyalkylene blockhaving a carboxyl group as the terminal group, or is obtained by acopolycondensation of a polyamide block having a carboxyl group as theterminal group and a polyoxyalkylene block having an amino group as theterminal group. Moreover, a polyether ester amide-series block copolymer(polyether polyamide block copolymer) is obtained by a polycondensationof a polyamide block having a carboxyl group as the terminal group and apolyoxyalkylene block having a hydroxyl group as the terminal group.Both of these copolymers are generally known as a polyamide elastomer.

Incidentally, commercially available polyamide elastomers hardly have anamino group in many cases. Throughout this specification, the polyamideblock copolymer includes a copolymer obtained by a copolycondensation ofthe above-described polyamide block and other block(s) (e.g., apolyether block, a polyester block, a polycarbonate block), in additiona polyamide block copolymer obtained by a polyaddition of variousdiisocyanates to at least one of a polyether block, a polyester blockand a polycarbonate block each having carboxyl groups at both terminals,if necessary under coexistence with the dicarboxylic acid component, anda decarboxylation of the resulting product.

Among the polyamide block copolymers, a polyether polyamide blockcopolymer, in particular a polyamide elastomer containing a polyethersegment as a soft segment, is preferred.

In the polyamide-series resin in the present invention, as an additionalresin (such as an aliphatic polyamide-series resin, an alicyclicpolyamide-series resin or an aromatic polyamide-series resin) suitablefor constituting a composition of the polyamide block copolymercomprising (containing) as the essential constitutive component thepolyether segment (A) having imino groups at both terminals, there maybe exemplified the following resins.

Among the aliphatic polyamide-series resins, the homopolyamide mayinclude a condensation product of an aliphatic diamine component [e.g.,a C₄₋₁₆alkylenediamine such as tetramethylenediamine,hexamethylenediamine, or dodecanediamine (preferably aC₄₋₁₄alkylenediamine, and particularly a C₆₋₁₂alkylenediamine)] and analiphatic dicarboxylic acid component [e.g., an alkylene dicarboxylicacid having about 4 to 20 carbon atoms, such as adipic acid, sebacicacid, or dodecanedioic acid (preferably a C₄₋₁₆alkylenedicarboxylicacid, and particularly a C₆₋₁₄alkylenedicarboxylic acid)], for example,a polyamide 46, a polyamide 66, a polyamide 610, a polyamide 612, and apolyamide 1010;a homopolyamide of a lactam [e.g., a lactam having about4 to 20 (preferably about 4 to 16) carbon atoms, such as ε-caprolactamor ω-laurolactam] or an aminocarboxylic acid [e.g., an aminocarboxylicacid having about 4 to 20 (preferably about 4 to 16) carbon atoms, suchas ω-aminoundecanoic acid], for example, a polyamide 6, a polyamide 11,and a polyamide 12;and others. Moreover, the copolyamide may include acopolyamide which is obtained by copolymerization of a constitutivecomponent capable of constituting a polyamide, e.g., the aliphaticdiamine components, the aliphatic dicarboxylic acid components, thelactams and the aminocarboxylic acids. Examples of the copolyamide mayinclude a copolymer of 6-aminocaproic acid and 12-aminododecanoic acid;a copolymer of 6-aminocaproic acid, 12-aminododecanoic acid,hexamethylenediamine and adipic acid; a copolymer ofhexamethylenediamine, adipic acid, hydrogenated dimer acid and12-aminododecanoic acid; a polyamide 6/11, a polyamide 6/12, a polyamide66/11, a polyamide 66/12;and others.

The alicyclic polyamide-series resin may include a homopolyamide orcopolyamide having at least part of one component selected from thegroup consisting of an alicyclic diamine and an alicyclic dicarboxylicacid as a constitutive component. For example, there may be used analicyclic polyamide obtained by using an alicyclic diamine and/or analicyclic dicarboxylic acid as at least one component among a diaminecomponent and a dicarboxylic acid component each constituting apolyamide-series resin. As the diamine component and the dicarboxylicacid component, the above-mentioned aliphatic diamine(s) and/oraliphatic dicarboxylic acid(s) are preferably used in combination withthe alicyclic diamine (s) and/or alicyclic dicarboxylic acid(s). Such analicyclic polyamide-series resin has high transparency, and is known asa so-called transparent polyamide.

Examples of the alicyclic diamine may include a diaminocycloalkane suchas diaminocyclohexane (e.g., a diaminoC₅₋₁₀cycloalkane); abis(aminocycloalkyl)alkane such as bis(4-aminocyclohexyl)methane,bis(4-amino-3-methylcyclohexyl)methane, or2,2-bis(4′-aminocyclohexyl)propane [e.g., abis(aminoC₅₋₈cycloalkyl)C₁₋₃alkane]; a hydrogenerated xylylenediamineand others. Moreover, the alicyclic dicarboxylic acid may include acycloalkanedicarboxylic acid such as cyclohexane-1,4-dicarboxylic acidor cyclohexane-1,3-dicarboxylic acid (for example, aC₅₋₁₀cycloalkane-dicarboxylic acid), and others.

Among the alicyclic polyamide-series resins, for example, a condensationproduct (a homo- or copolyamide) of the aliphatic dicarboxylic acid andthe alicyclic diamine is preferred.

The aromatic polyamide-series resin may include a polyamide in which atleast one component of the aliphatic diamine component and the aliphaticdicarboxylic acid component in the above aliphatic polyamide comprisesan aromatic component, for example, a polyamide having an aromaticcomponent in a diamine component [for example, a condensation product ofan aromatic diamine (e.g., metaxylylenediamine) and an aliphaticdicarboxylic acid, such as MXD-6], a polyamide having an aromaticcomponent in a dicarboxylic acid component [e.g., a condensation productof an aliphatic diamine (e.g., trimethylhexamethylenediamine) and anaromatic dicarboxylic acid (e.g., terephthalic acid, isophthalic acid)],and others.

The above-mentioned blendable polyamide-series resin may further includea polyamide comprising a dimer acid as a dicarboxylic acid component, apolyamide in which a branched chain structure is introduced by using asmall amount of a polyfunctional polyamine and/or polycarboxylic acidcomponent, a modified polyamide (e.g., a N-alkoxymethylpolyamide), and acomposition thereof, and others.

In the molded composite article of the present invention, the numberaverage molecular weight of the polyamide-series resin (e.g., thepresent invention-related polyamide block copolymer having in a moleculethereof the polyether segment (A) having imino groups at both terminalsas the essential constitutive component, and a blend or alloy of thepolyamide block copolymer with the above-mentioned extensivepolyamide-series resin) is about 6,000 to 100,000, preferably about8,000 to 50,000, and more preferably about 10,000 to 30,000.

In the present invention, in the case where the polyamide-series resinconstituting the resin member (Ia) comprises a polyamide block copolymerhaving in a molecule thereof the polyether segment (A) having iminogroups at both terminals as the essential constitutive component, or acomposition containing the polyamide block copolymer as the maincomponent, significantly high bonded strength is achieved in thecomposite article of the present invention which comprises the resinmember (Ia) and the resin member (IIa) comprising a thermoplasticpolyurethane-series resin, in comparison with case where thepolyamide-series resin comprises a polyamide block copolymer free from(excluding) the polyether segment (A) having imino groups at bothterminals as the constitutive component. In particular, in the casewhere the polyether segment (A) having imino groups at both terminalscomprises as the base component a condensation product (condensate) ofan aliphatic diol having 2 to 8 carbon atoms, more preferably analiphatic diol having 2 to 4 carbon atoms, and more preferably analiphatic diol having 2 to 3 carbon atoms, higher bonded strengthbetween the resin members (Ia) and (IIa) is realized.

In the molded composite article of the present invention, thepolyamide-series resin may be a polyamide-series resin having an aminogroup. As described above, in the present invention, the resin member(Ia) comprising a polyamide-series resin is directly bonded to the resinmember (IIa) comprising a thermoplastic polyurethane-series resin toform a molded composite article. In this regard, the polyamide-seriesresin basically comprises a polyamide block copolymer having in apolymer molecule thereof a polyether segment (A) having imino groups atboth terminals as the essential constitutive component. In addition, thespecific concentration of the free amino group in the polyamide-seriesresin realizes further improvement in bonded strength of the compositearticle comprising the resin member (Ia) and the resin member (IIa).

The amino group usually shows a free amino group (—NH₂ group) andusually does not include a —NH— (imino) group and —N< group derived froman amide bond constituting the main chain of the polyamide-series resin,a urea bond, a urethane bond and other bonds. The free amino group mayexist at terminal(s) or branched chain of the polyamide block copolymermolecule in the present invention, or may exist at terminal(s) orbranched chain of additional (another) polyamide resin for compoundingwith the polyamide block copolymer in the present invention to form ablend or alloy. Further, in addition to the above, the polyamide-seriesresin constituting the resin member (Ia) may comprise a compound havinga free amino group to be mixed therewith.

The content (or concentration) of the amino group (or amino groupconcentration) in the polyamide-series resin constituting the resinmember (Ia) is, relative to 1 kg of the polyamide-series resin, not lessthan 10 mmol (e.g., about 10 to 300 mmol), preferably not less than 15mmol (e.g., about 15 to 200 mmol), more preferably not less than 20 mmol(e.g., about 20 to 150 mmol), and particularly not less than 30 mmol(e.g., about 30 to 100 mmol). The polyamide-series resin preferablycontains a terminal amino group at a range of such a content.

The content of the amino group may be adjusted by a conventional method,for example, (a) a method of adjusting a proportion of a diaminecomponent constituting a polyamide-series resin; (b) a method of forminga blend or alloy by combining a plurality of polyamide-series resinsdifferent in amino group concentration from each other (e.g., by using apolyamide-series resin having an amino group at a low concentration incombination with a polyamide-series resin having an amino group at ahigh concentration). Moreover, the content of the amino group may beadjusted by making the polyamide-series resin having an amino group intoa polyamide-series resin composition which contains a polyamide blockcopolymer containing the polyether segment (A) (hereinafter, sometimessimply referred to as a polyamide-series resin). In such apolyamide-series resin composition, for example, the content of theamino group may be adjusted by (c) a method of involving (C) a compoundhaving a free amino group (or amine compound, e.g., an amine compoundhaving an amino group at a high concentration and having a relativelylow molecular weight) in the polyamide-series resin (e.g., a polyamidehaving a terminal amino group at a low concentration); or others. Morespecifically, for example, in a copolycondensation of a block havingamino groups at the both terminals with a block having carboxyl groupsat both terminals, introduction of an amino group into the polyamideblock copolymer may be conducted by increasing the proportion of theblock having amino groups at both terminals, or by adding an aminecompound (e.g., the above mentioned aliphatic diamine, alicyclicdiamine, and aromatic diamine; a monoamine; a polyamide oligomer; and apolyamide-series resin) in an adequate amount.

In the case where the polyamide-series resin comprises a polyamide resinalone, the amino group concentration may be adjusted by a method such asthe above-mentioned method (a). Moreover, in the case where thepolyamide-series resin is a mixture which contains a plurality ofpolyamide-series resins and is prepared by the above-mentioned method(b), the amino group concentration of each polyamide-series resin may besuitably adjusted by the method (a) and/or (c) as described above.

When the polyamide-series resin is a polyamide resin alone (e.g., aresin prepared by the method (a)), or a mixture containing a pluralityof polyamide-series resins different in amino group concentration fromeach other (e.g., a mixture prepared by the method (b)), the amino groupconcentration of the polyamide-series resin is, for example, not lessthan 20 mmol/kg (e.g., about 20 to 300 mmol/kg), preferably not lessthan 40 mmol/kg (e.g., about 40 to 200 mmol/kg), more preferably notless than 60 mmol/kg (e.g., about 60 to 150 mmol/kg), and particularlynot less than 70 mmol/kg (e.g., about 70 to 100 mmol/kg).

In the case using combination of a plurality of polyamide-series resinsdifferent in amino group concentration from each other, the totalcontent of the amino group in the polyamide-series resins may, forexample, be adjusted by using a polyamide-series resin having an aminogroup concentration of about 0 to 30 mmol/kg (e.g., about 0 to20mmol/kg) in combination with a polyamide-series resin having an aminogroup concentration of about 40 to 400 mmol/kg (preferably about 50 to300 mmol/kg, and particularly about 100 to 200 mmol/kg). The proportionof the polyamide-series resin having an amino group at a higherconcentration may for example be about 1 to 60 parts by weight,preferably about 5 to 50 parts by weight, and more preferably about 10to 40 parts by weight relative to 100 parts by weight of thepolyamide-series resin having an amino group at a lower concentration.

Moreover, in the case where the polyamide-series resin is a resincomposition comprising the polyamide resin and an amine compound (e.g.,a composition prepared by the method (c)), the amino group concentrationof the polyamide-series resin may for example be not less than 10mmol/kg (e.g., about 10 to 300 mmol/kg), preferably not less than 20mmol/kg (e.g., about 20 to 200 mmol/kg), more preferably not less than40 mmol/kg (e.g., about 40 to 150 mmol/kg), and particularly not lessthan 50 mmol/kg (e.g., about 50 to 100 mmol/kg).

As the amine compound (the compound (C) having a free amino group),there may be used an amine compound having a relatively low molecularweight, such as a monoamine, a polyamine [e.g., a diamine (for example,the above-mentioned aliphatic diamines, alicyclic diamines and aromaticdiamines), in addition, a polyamine such as an aliphatic polyamine(e.g., diethylenetriamine)], and a polyamide oligomer; apolyamide-series resin (the above exemplified polyamide-series resinhaving a free amino group); and others. The amine compounds may be usedsingly or in combination. Among these compounds, the polyamide oligomeris particularly preferred.

As the polyamide oligomer, there may be used a polyamide having arelatively low molecular weight, which is obtained by a conventionalmanner, for example, by adjusting polycondensation or other conditionsand using the above-mentioned polyamide component(s). For example, asthe polyamide component to be a raw material, there may be used acombination of the above-mentioned diamine [e.g., an aliphatic diamine(e.g., an alkylenediamine), an alicyclic diamine, an aromatic diamine]and a dicarboxylic acid (e.g., an aliphatic dicarboxylic acid, anaromatic dicarboxylic acid), a combination of the above-mentioneddiamine and/or dicarboxylic acid and a lactam (e.g., a lactam havingabout 4 to 20 carbon atoms, such as ω-laurolactam), and othercombinations. The polyamide oligomer may be obtained by for examplepolymerizing the lactam and the aliphatic diamine with heating andstirring under an applied pressure.

The number average molecular weight of the polyamide oligomer is, forexample, about 500 to 10,000, preferably about 500 to 8,000 (e.g., about1,000 to 7,000), more preferably about 1,000 to 5,000, and usually about2,000 to 6,000 (e.g., about 3,000 to 6,000).

The polyamide oligomer may have an amino group at least at one terminalof the main chain, for example, may have amino groups at both terminalsof the main chain. Moreover, the polyamide oligomer may have an aminogroup at a branched chain thereof.

The amine compound (particularly a polyamide oligomer) is preferablyused in combination with a resin such as the aliphatic polyamide-seriesresin, the alicyclic polyamide-series resin or the polyamide blockcopolymer, as the base polyamide resin.

In the case where the polyamide-series resin comprises an amine compoundin combination, the total content of the amino group in thepolyamide-series resin (or composition) may be adjusted, for example, byusing a polyamide-series resin having an amino group concentration ofabout 0 to 30 mmol/kg (preferably about 0 to 20 mmol/kg) in combinationwith an amine compound having an amino group concentration of about 40to 1000 mmol/kg (preferably about 50 to 700 mmol/kg, and particularlyabout 100 to 500 mmol/kg).

The proportion of the amine compound may be controlled so that thecontent of the amino group in the polyamide-series resin is includedwithin the above-described range. For example, the proportion of theamine compound (e.g., the polyamide oligomer) is, for example, not morethan 10 parts by weight (about 0.01 to 10 parts by weight), preferablyabout 0.1 to 8 parts by weight, and particularly not more than 7 partsby weight (about 0.5 to 7 parts by weight) relative to 100 parts byweight of the base polyamide resin (a polyamide-series resin having anamino group at a low concentration). Too large proportion of the aminecompound has a possibility of deteriorating resin properties, inparticular in the case of using the polyamide-series resin as a hardresin.

Moreover, the proportion of the amine compound (a compound having a freeamino group (C)) may be, in the polyamide-series resin composition,about 0.01 to 20% by weight, preferably about 0.1 to 15% by weight, andmore preferably about 0.5 to 10% by weight (e.g., about 1 to 8% byweight).

In order to further enhance the bonded strength between thepolyamide-series resin member (e.g., a hard resin member) and thethermoplastic polyurethane-series resin member (e.g., a soft resinmember), the enthalpies of fusion and crystallization of thepolyamide-series resin may be not more than 100 J/g (e.g., about 0 to100 J/g), preferably not more than 80 J/g (e.g., about 0 to 80 J/g), andmore preferably not more than 70 J/g (e.g., about 0 to 70 J/g).According to the present invention, even using a polyamide-series resinhaving a low degree of crystallinity, certain and efficient bonding (orjoining) can be achieved. The enthalpies of fusion and crystallizationin such a polyamide-series resin may for example be selected from arange of not more than 30 J/g (e.g., about 0 to 30 J/g), preferably notmore than 20 J/g (e.g., about 0 to 20 J/g), and more preferably not morethan 17 J/g (about 0 to 17 J/g).

Incidentally, the “enthalpies of fusion and crystallization” of thepolyamide-series resin denotes a value obtained by subtracting a heat ofcrystallization (ΔHf) generated along with crystallization of a resinfrom a heat of fusion (ΔHm) necessary to melt the resin. That is, in ameasurement of the heat of fusion, if both the heat of crystallizationand the following heat of fusion are observed along with raising thetemperature, the enthalpies of fusion and crystallization of thepolyamide-series resin is assessed as a value subtracted the found valueΔHf of the heat of crystallization per one gram of the resin from thefound value ΔHm of the heat of fusion per one gram of the resin. Theenthalpies of fusion and crystallization can be measured by adifferential scanning calorimeter (DSC apparatus) based on JIS (JapaneseIndustrial Standards) K 7122. Incidentally, since the heat ofcrystallization cannot be observed in a fully amorphous polyamide, theenthalpies of fusion and crystallization of such a polyamide isqualified as 0 J/g.

The polyamide-series resin having such enthalpies of fusion andcrystallization, in particular a polyamide-series resin havingenthalpies of fusion and crystallization of not more than 20 J/g (e.g.,a transparent polyamide) may be molded by a known molding method. Thefurther details about of such a polyamide-series resin may for examplebe referred to Japanese Patent Application Laid-Open No. 239469/1996(JP-8-239469A), Japanese Patent Application Laid-Open No. 1544/2000(JP-2000-1544A), and others.

Incidentally, the concentration of the carboxyl group (or carboxyl groupconcentration) in the polyamide-series resin is not particularly limitedto a specific one, and may for example be about 0.1 to200 mmol/kg,preferably about 0.5 to 150 mmol/kg, and more preferably about 1 to 100mmol/kg.

In such a range that the effects of the present invention are notdeteriorated, the polyamide-series resin member may comprise otherresin(s) [for example, a thermoplastic resin such as a polyester-seriesresin, a polycarbonate-series resin, a polysulfone-series resin, apolyimide-series resin, a polyketone-series resin, a polyolefinic resin,a styrenic resin, a (meth)acrylic resin, or a halogen-containingvinyl-series resin)], various additives [for example, a filler orreinforcing agent (e.g., a reinforcing fiber), a stabilizer (e.g., anultraviolet ray absorbing agent, an antioxidant, and a heat stabilizer),a coloring agent, a plasticizer, a lubricant, a flame retardant, and anantistatic agent].

Incidentally, in accordance with the production of the molded compositearticle of the present invention, a “warp” sometimes occurs in theproduct depending on the difference between mold shrinkage factors ofthe resin members. In the case where the degree of the correction forthe warp is large, the bonding part of resin members may be broken, orthe generation of stress crack in each resin member occurs. Therefore,the polyamide-series resin preferably has lower crystallinity. The finalcrystallinity degree (mean final crystallinity degree) of thepolyamide-series resin is advantageously not more than 50% (e.g., about5 to 50%), preferably not more than 40% (e.g., about 5 to 40%), and morepreferably not more than 30% (e.g., about 10 to 30%). In the case wherea polyamide homopolymer is taken as an example and the finalcrystallinity degree is compared, the final crystallinity degree becomessmaller in the following order.

polyamide 66>polyamide 6≧polyamide 612>polyamide 11≦polyamide 12

Incidentally, considering only the final crystallinity degree, thecopolymer is more advantageous than the homopolymer. Further, in generalthe copolymer is also more advantageous than the homopolymer from theperspective that the copolymer is superior to the homopolymer inflexibility.

In the case of the polyamide block copolymer (a polyamide elastomer)which comprises a polyamide homopolymer as the hard segment and apolyether as the soft segment, the final crystallinity degree can beadjusted by the ratio of the hard segment and the soft segment. In thecase where the final crystallinity degree of the polyamide blockcopolymer is adjusted to not more than 40% (e.g., about 5 to 40%),preferably not more than 35% (e.g., about 5 to 35%) and more preferablynot more than 30% (e.g., about 10 to 30%), such apolyamide blockcopolymer can provide a flexibility which resembles to that of thethermoplastic polyurethane-series resin.

Incidentally, the term “the final crystallinity degree” means a degreeof crystallinity measured by an X-ray diffraction analysis using a flatplate 1 mm thick, where the flat plate is formed by heating a sampleresin to a temperature which is 20° C. higher than a melting pointthereof, and then cooling the resin to a room temperature at a rate of3° C./minute by means of a precision (or accurate) heat pressingmachine. The melting point of the resin is measured by a differentialscanning calorimeter (DSC apparatus) in accordance with JIS K 7122.

(Polyurethane-series Resin)

The thermoplastic polyurethane-series resin may be obtained by reactinga diisocyanate, a diol and, if necessary, a chain-extension agent.

Example of the diisocyanate may include an aliphatic diisocyanate suchas hexamethylene diisocyanate (HMDI), or 2,2,4-trimethylhexamethylenediisocyanate; an alicyclic diisocyanate such as 1,4-cyclohexanediisocyanate, dicycloalkylmethane-4,4′-diisocyanate, or isophoronediisocyanate (IPDI); an aromatic diisocyanate such as phenylenediisocyanate, tolylene diisocyanate (TDI), ordiphenylmethane-4,4′-diisocyanate (MDI); an araliphatic diisocyanatesuch as xylylene diisocyanate; and others. As the diisocyanate, theremay also be used a compound having an alkyl group (e.g., methyl group)substituted on a main chain or ring thereof. The diisocyanate(s) may beused singly or in combination.

Examples of the diol may include a polyester diol [for example, apolyester diol (aliphatic polyester diol) derived from an aliphaticdicarboxylic acid component (e.g., a C₄₋₁₂aliphatic dicarboxylic acidsuch as adipic acid), an aliphatic diol component (e.g., aC₂₋₁₂aliphatic diol such as ethylene glycol, propylene glycol,butanediol, or neopentyl glycol), and/or a lactone component (e.g., aC₄₋₁₂lactone such as ε-caprolactone); for example, a poly(ethyleneadipate), a poly(1,4-butylene adipate), and a poly(1,6-hexyleneadipate), a poly-ε-caprolactone], a polyether diol [for example, analiphatic polyether diol, e.g., a poly(oxyC₂₋₄alkylene)glycol such as apoly(oxyethylene)glycol, a poly(oxytrimethylene)glycol, apoly(oxypropylene)glycol or a poly(oxytetramethylene)glycol, and a blockcopolymer of the poly(oxyalkylene)glycol (e.g., apolyoxyethylene-polyoxypropylene block copolymer); an aromatic polyetherdiol, e.g., an adduct of an aromatic diol with an alkylene oxide, suchas a bisphenol A-alkylene oxide adduct (e.g., an adduct of aC₂₋₄alkylene oxide such as ethylene oxide, or propylene oxide)]; apolyester ether diol (a polyester diol obtained by using the polyetherdiol as part of a diol component); and others. The diol(s) may be usedsingly or in combination. Among these diols, the polyester diol or thepolyether diol is used in many cases, and among the polyether diols, apolytetramethylene ether glycol practically used.

As the chain-extension agent, there may be used a glycol [for example, ashort chain glycol, e.g., a C₂₋₁₀alkanediol such as ethylene glycol,propylene glycol, 1,4-butanediol, or 1,6-hexanediol; and abishydroxyethoxybenzene (BHEB)], and in addition a diamine [for example,an aliphatic diamine such as a C₂₋₁₀alkylenediamine, e.g.,ethylenediamine, trimethylenediamine, tetramethylenediamine, orhexamethylenediamine; an alicyclic diamine such as isophorone diamine;an aromatic diamine such as phenylenediamine or xylylenediamine]. Thechain-extension agent(s) may be used singly or in combination.

The thermoplastic polyurethane-series resin also may include a perfectthermoplastic polyurethane obtained by using a diol and a diisocyanateat a substantially equivalent amount, and an imperfect thermoplasticpolyisocyanate having a small amount of a residual free (or unreacted)isocyanate, which is obtained by using a slightly excess amount of adiisocyanate relative to a diol

Among the thermoplastic polyurethane-series resins, in particular, thethermoplastic polyurethane elastomer is preferred, which is obtained byusing a diol [e.g., a diol having a polyester unit or a polyether unit],a diisocyanate, and a glycol (e.g., a short chain glycol) as thechain-extension agent. The thermoplastic polyurethane elastomercomprises a hard segment (hard block) which comprises a polyurethanecomprising a glycol and a diisocyanate, and a soft segment (soft block)which comprises an aliphatic polyether diol (e.g., a poly(oxyethylene)glycol), an aliphatic polyester diol and others. The polyurethaneelastomer may include, for example, a polyether urethane elastomer, apolyester ether urethane elastomer, a polycarbonate urethane elastomer,and others, depending on the species of the soft segment.

These thermoplastic polyurethane-series resins may be used singly or incombination.

In such a range that the effects of the present invention are notdeteriorated, the thermoplastic polyurethane-series resin member maycomprise other resin(s) (e.g., a thermoplastic resin, particularly athermoplastic elastomer such as a polyamide-series elastomer, apolyester-series elastomer, or a polyolefinic elastomer), a stabilizer(e.g., a heat stabilizer, an ultraviolet ray absorbing agent and anantioxidant), a plasticizer, a lubricant, a filler, a coloring agent, aflame retardant, an antistatic agent, and others.

In such a molded composite article of the present invention, thepolyamide-series resin and the thermoplastic polyurethane-series resinare firmly bonded together without an adhesive. The bonded strength isusually not less than 30 N/cm, and cohesive failure sometimes occursalong with separation of the polyamide-series resin member (e.g., a hardresin member) from the thermoplastic polyurethane-series resin member(e.g., a soft resin member). The bonded strength of such a moldedcomposite article is usually 30 N/cm to cohesive failure, preferably notless than 40 N/cm, and particularly not less than 50 N/cm (50 N/cm tocohesive failure).

[Production Process of Molded Composite Article]

The molded composite article of the present invention may be produced bybonding the polyamide-series resin or (Ia) a resin member thereof to thethermoplastic polyurethane-series resin or (IIa) a resin member thereofunder heating. In usual, the molded composite article may be practicallyproduced by heating at least one selected from the group consisting of(i) the polyamide-series resin or the resin member thereof (Ia) and (ii)the thermoplastic polyurethane-series resin or the resin member thereof(IIa) to bond the former (i) to the latter (ii). In the preferredembodiment, the molded composite article may be produced by heating atleast one selected from the group consisting of (i) the polyamide-seriesresin or the resin member thereof (Ia) and (ii) the thermoplasticpolyurethane-series resin or the resin member thereof (IIa) to be moltenwith bringing former (i) into contact with the latter (ii) to bond bothresins (or resin members) together. Such a molded composite article mayfor example be produced by bonding (e.g., thermal-welding) the hardresin (e.g., the polyamide-series resin) to the soft resin (e.g., thethermoplastic polyurethane-series resin) in a molding process by meansof a conventional method such as a thermoforming (e.g., a heat pressmolding, an injection press molding), a vacuum molding, an injectionmolding (e.g., an insert injection molding, a two-color (or double)injection molding, a core-back injection molding, a sandwich injectionmolding), an extrusion molding (e.g., a co-extrusion molding, a T-dielamination molding), or a blow molding.

For example, the molding method such as an insert molding or aninjection press molding may comprise heating the thermoplasticpolyurethane resin to be molten with bringing the thermoplasticpolyurethane resin in the molten state into contact with at least partof a resin member comprising the polyamide-series resin to bond thethermoplastic polyurethane resin to the polyamide-series resin member,or heating the polyamide-series resin to be molten with bringing thepolyamide-series resin in the molten state into contact with at leastpart of a resin member comprising the thermoplastic polyurethane-seriesresin to bond the polyamide-series resin to the thermoplasticpolyurethane resin member. Moreover, the molding method such as a doubleinjection molding or a co-extrusion molding may comprise heating both ofthe polyamide-series resin and the thermoplastic polyurethane-seriesresin to be molten with bringing the polyamide-series resin in themolten state into contact with the thermoplastic polyurethane-seriesresin in the molten state to bond both resins together. A moldedcomposite article in which the polyamide-series resin member and thepolyurethane-series resin member are firmly bonded together can beobtained by heating at least one resin selected from thepolyamide-series resin and the polyurethane-series resin to be moltenwith bringing the polyamide-series resin into contact with thethermoplastic polyurethane-series resin, bonding both resins together,and usually cooling the resulting (bonded) matter. Moreover, dependingon a purpose and an application, it is sufficient to bond thepolyamide-series resin member to the thermoplastic polyurethane-seriesresin member at least in part.

Incidentally, the resin can be molten by heating the resin to atemperature of not lower than a melting point thereof. In the case of asubstantially uncrystallized resin, the resin can be molten by heatingthe resin to a temperature of not lower than a glass transition point(Tg) thereof.

According to the present invention, since the specific polyamide-seriesresin is employed, the bonded strength can be significantly improvedeven in a molded composite article obtained from a different kind ofmaterials. Accordingly, the present invention ensures such a high-levelbonded strength that cannot be obtained from a physical action due tosimple thermal welding. Therefore, throughout of this specification,“thermal welding” includes not only simple thermal welding, but alsothermal welding (thermal bonding) including a chemical reaction.

As described above, it is not particularly limited which of thepolyamide-series resin or the polyurethane-series resin is molten. Themethod (or process) may comprise heating a soft resin having a lowermelting point or glass transition point (Tg), and bonding the soft resinto a hard resin member comprising a hard resin having a higher meltingpoint or Tg; or comprise heating a hard resin having a higher meltingpoint or Tg, and bonding the hard resin to a soft resin membercomprising a soft resin having a lower melting point or Tg. Among thesemethods, in particular, the former method has an advantage overconventional techniques since the effects of the present invention arecharacteristically and effectively exhibited. On the contrary, theconventional method with the use of simple physical thermal weldingcomprises melting (fusing) the surface of the precedently molded member(mainly a polyamide-series resin member) by heat (heat from the resin ina molten state) of the subsequently molded resin (mainly apolyurethane-series resin) and bonding both resins together. In such acase, the molding temperature of the polyurethane-series resinfrequently becomes lower than the melting point of the precedentlymolded polyamide-series resin. Moreover, even when the moldingtemperature of the polyurethane-series resin is higher than the meltingpoint of the polyamide-series resin, the heat quantity is ofteninsufficient to melt the surface of the polyamide-series resin member.Therefore, the conventional techniques usually never comprise such acase that the polyamide-series resin member is molded prior to moldingthe polyurethane-series resin. However, even in the above case,according to the present invention, since the polyamide-series resin andthe thermoplastic polyurethane-series resin can be more easily bondedtogether, the present invention can increase the freedom of theproduction process of the molded composite article and can alsorationalize (labor- or power-save) the process step to a large degree.

In the present invention, in many cases, the hard resin usuallycomprises the polyamide-series resin and the soft resin usuallycomprises the thermoplastic polyurethane-series resin. Moreover, it isalso feasible that the hard resin may comprise the thermoplasticpolyurethane-series resin and the soft resin may comprise thepolyamide-series resin. Moreover, the hardness of the polyamide-seriesresin may be in the same level as that of the thermoplasticpolyurethane-series resin.

To be more precise, in the heat press molding, the molded compositearticle may be produced by melting at least one resin selected from thegroup consisting of the hard resin (or composition) and the soft resin(or composition) in a metal mold of the press molding, bringing oneresin (or composition) into contact with the other resin (orcomposition) under an applied pressure, and bonding both resins (orcompositions) together. In the heat press molding, the hard resin and/orthe soft resin may be filled into the metal mold in a pellet form, apowdered form or other form(s), or may be loaded to the metal mold as amolded article precedently formed by other molding method.

In the insert injection molding, the molded composite article may beproduced by molding any one of the hard resin (or resin composition) orthe soft resin (or resin composition), usually the hard resin, with theuse of a molding method (such as an injection molding, an extrusionmolding, a sheet molding or a film molding), inserting or putting thusshaped molded article in a metal mold, and then injecting the otherresin, usually the soft resin, to the space or cavity between the moldedarticle and the metal mold. In the insert injection molding, the moldedarticle to be inserted in the metal mold is preferably pre-heated ashigh as possible.

In the two-color (or double) injection molding, a molded compositearticle may be produced by injecting any one component of the hard resin(or resin composition) or the soft resin (or resin composition), usuallythe hard resin, to a metal mold by means of two injection moldingmachines or more, and exchanging cavity of the metal mold by rotation ormovement of the metal mold, and injecting the other component, usuallythe soft resin, to the space or cavity between thus obtained moldedarticle and the metal mold.

In the core-back injection molding, a molded composite article may beproduced by injecting any one component of the hard resin (or resincomposition) or the soft resin (or resin composition), usually the hardresin, in a metal mold, enlarging the cavity of the metal mold, andinjecting the other component, usually the soft resin, to the space orcavity between thus obtained molded article and the metal mold.

Among these molding methods, particularly from the viewpoint of massproduction or other properties, suitable methods includes, for example,the heat press molding such as injection press moldings, and theinjection molding (e.g., insert injection moldings, double injectionmoldings, core-back injection moldings and sandwich injection moldings).

In the thermal welding, the melting temperature (or thermal weldingtemperature) of the hard resin and/or soft resin may be selecteddepending on the species of the both resins (or resin compositions), andmay for example be selected within a range of about 100 to 250° C.,preferably about 120 to 230° C., and more preferably about 150 to 220°C.

The structure and shape of the molded composite article is notparticularly limited to a specific one, and may be a structure suitablefor design, decorative property, touch or others. For example, such astructure may be obtained by coating or laminating part or all of thesoft resin member with the hard resin member, and usually, preferablyobtained by coating or laminating part or all of the hard resin memberwith the soft resin member (for example, obtained by coating contactpart of the hard resin member with human body (such as a hand), with thesoft resin member). Moreover, the concrete structure may include, forexample, a two-dimensional structure (such as a sheet-like form or aplate-like form), and a three-dimensional structure (such as astick-like form, a tube-like form, a casing or a housing).

According to the present invention, the hard resin and the soft resincan be directly and firmly bonded together by thermal welding without(going through) complicated production steps (e.g., a step for creatinga concavo-convex site in the composite area, a step for applying orcoating with an adhesive). Therefore, the present invention ensures toconveniently obtain a molded composite article improved in propertiessuch as design, decorative property, or good touch or texture (e.g.,soft texture, flexibility).

INDUSTRIAL APPLICABILITY

The molded composite article of the present invention may be used asvarious industrial components (or parts), for example, an automotivepart (e.g., an automotive interior part such as an instrument panel, acenter panel, a center console box, a door trim, a pillar, an assistgrip, a steering wheel or an air bag cover; an automotive exterior partsuch as a lacing or a bumper; an automotive functional component such asa rack and pinion boot, a suspension boot or a constant velocity jointboot), a household electrical part (e.g., a cleaner bumper, a switch ofa remote control, and a key top of office automation (OA) apparatus), aproduct to be used in water (e.g., swimming goggles, and a cover of aunderwater camera), an industrial part (e.g., a cover part; variousindustrial parts equipped with a packing for the purpose of sealingproperty, water proofing property, sound insulating property, vibrationinsulating property, or other properties; an industrial rubber roller),an electric or electronic device part (e.g., a curl cord wire covering,a belt, a hose, a tube and a sound deadening gear), sports goods, shoegoods (e.g., athletic shoes, and a shoe sole), and a part requiringdesign or decorative property (e.g., dark glasses, and glasses).

Among them, the molded composite article is particularly suitable for aconstitutive member of the shoe or the roll (e.g., a rubber roller). Theconstitutive member of the shoe includes a shoe part such as a shoe sole(sole), and others. Moreover, the molded composite article may form (orconstitute) athletic shoes, work shoes (e.g., boots, rain shoes, shoesfor gardening). In the shoe application, a combination of a hard orglass fiber-reinforced polyamide-series resin and a softpolyurethane-series resin becomes easy, although such a combination wastroublesome in the past. Accordingly, the molded composite articlegreatly contributes to improvement in design or functionality of theshoe.

Further, in the roll (e.g., a rubber roller) application, for example,the roll may comprise an axis (shaft) in which at least the surfacelayer comprises a polyamide-series resin, and a thermoplasticpolyurethane-series resin layer formed along the surrounding surface ofthe axis. The axis may be obtained by forming a polyamide-series resinlayer on the surface of the metal shaft, or may be an axis comprising apolyamide-series resin. In such a roller application, since a cuttingfinish for obtaining a shaft precision and a surface finish of athermoplastic polyurethane-series resin can be conducted in oneoperation by the same grinding machine, the production process of theroller can be significantly abbreviated and the cost can be dramaticallyreduced.

EXAMPLES

The following examples are intended to describe this invention infurther detail and should by no means be interpreted as defining thescope of the invention. Incidentally, the attributes (characteristicvalues) were measured in the following manner.

(1) Concentration of the terminal amino group ([NH₂]): A polymer (about1 g) was dissolved in 40 mL of a mixed solvent of phenol/methanol (ratioby volume: 9/1). To thus obtained sample solution was added Thymol Blue(thymolsulfonphthalein) as an indicator, and the sample solution wastitrated with a 1/20 N (0.05 N) hydrochloric acid.

(2) The melting point (T_(m)) was measured under an atmosphere ofnitrogen with “DSC220C” manufactured by Seiko Instruments Inc, withheating a polyamide-series resin to 250° C. from a room temperature at aheating rate of 10° C./min (called as “first heating run”) andmaintaining the temperature at 250° C. for 10 minutes, subsequentlycooling the resin from 250° C. to −80° C. at a cooling rate of 10°C./min (called as “first cooling run”), and then heating the resin from−80° C. to 250° C. at a heating rate of 10° C./min (called as “secondheating run”). The endothermic peak temperature in the second heatingrun was regarded as the melting temperature (T_(m)) of thepolyamide-series resin.

(3) Bonded strength: From each of the polyurethane elastomer and thepolyamide-series material, films having a field of 10×10 cm and athickness of 0.5 mm were prepared by a heat press molding. Subsequently,these films were pressed for 10 minutes under a pressure of 400 kgf/cm²at a predetermined temperature (three kinds of temperature, i.e.,T_(m)+10° C., T_(m)° C., T_(m)−10° C.) shown in Table 1. In thepressing, an aluminium foil was interposed between the polyurethaneelastomer (TPU) film and the polyamide-series material film by 3 cm fromthe edge so as to provide a place for setting a tensile fixture (joint)to be used in the subsequent peel test.

Thus obtained composite film was cut into a strip specimen having a sizeof 2 cm in width, and then the strip specimen was subject to the peeltest (tensile test). Thus determined strength was regarded as the bondedstrength of the composite film. The tensile test was conducted with“RTA-1T” manufactured by ORIENTEC Co., LTD. at a tensile speed of 50mm/min. The bonded strength was calculated by the following formula:Bonded strength [unit: N/cm]=(Actually measured strength) [unit: N]/2[unit: cm].

Incidentally, the following polyurethane elastomers were used as thepolyurethane elastomer (TPU).

-   [TPU-01] “C90A10” manufactured by BASF: a polyurethane elastomer    having an ester-series soft segment-   [TPU-02] “ET885-10” manufactured by BASF: a polyurethane elastomer    having an ether-series soft segment.

Example 1

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressure regulatorand a polymer dispenser, were charged 12-aminododecanoic acid (15 kg), apolyethylene glycol (0.8 kg) having amino groups at both terminals(Trade name “XTJ-504” manufactured by Suntechno Chemical Co.), andadipic acid (0.637 kg). After the vessel was sufficiently purged withnitrogen, the vessel was gradually heated from a room temperature to235° C. over 3 hours with supplying nitrogen gas at a flow rate of 300L/minute, subsequently the polymerization was conducted for 7 hours withkeeping conditions. The pressure in the vessel was adjusted to 0.05 MPaafter starting heating. Then, after stopping the agitation, a moltenpolymer was taken from the polymer dispenser. After water-cooling themolten polymer, the cooled polymer was pelletarized to obtain a pellet(about 13 kg). Thus obtained polymer had the terminal amino groupconcentration of [NH₂]=31 mmol/kg, and the melting point of T_(m)=168°C.

Example 2

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(15 kg), a polyglycol (4.363 kg) having amino groups at both terminals(Trade name “XTJ-542” manufactured by Suntechno Chemical Co.), andadipic acid (0.637 kg). After the vessel was sufficiently purged withnitrogen, the vessel was gradually heated from a room temperature to235° C. over 3 hours with supplying nitrogen gas at a flow rate of 300L/minute, subsequently the polymerization was conducted for 7 hours withkeeping conditions. The pressure in the vessel was adjusted to 0.05 MPaafter starting heating. Then, after stopping the agitation, a moltenpolymer was taken from the polymer dispenser. After water-cooling themolten polymer, the cooled polymer was pelletarized to obtain a pellet(about 13 kg). Thus obtained polymer had the terminal amino groupconcentration of [NH₂]=37 mmol/kg, and the melting point of Tm =165° C.

Example 3

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(11.2 kg), a polyethylene glycol (1.15 kg) having amino groups at bothterminals (Trade name “XTJ-504” manufactured by Suntechno Chemical Co.),and adipic acid (1.12 kg). After the vessel was sufficiently purged withnitrogen, the vessel was gradually heated from a room temperature to235° C. over 3 hours with supplying nitrogen gas at a flow rate of 300L/minute, subsequently the polymerization was conducted for 7 hours withkeeping conditions. The pressure in the vessel was adjusted to 0.05 MPaafter starting heating. Then, after stopping the agitation, a moltenpolymer was taken from the polymer dispenser. After water-cooling themolten polymer, the cooled polymer was pelletarized to obtain a pellet(about 11 kg). Thus obtained polymer had the terminal amino groupconcentration of [NH₂]=23 mmol/kg, and the melting point of Tm =168° C.

Example 4

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(17 kg), a polyglycol (2.6 kg) having amino groups at both terminals(Trade name “XTJ-542” manufactured by Suntechno Chemical Co.), andadipic acid (0.38 kg). After the vessel was sufficiently purged withnitrogen, the vessel was gradually heated from a room temperature to235° C. over 3 hours with supplying nitrogen gas at a flow rate of 300L/minute, subsequently the polymerization was conducted for 7 hours withkeeping conditions. The pressure in the vessel was adjusted to 0.05 MPaafter starting heating. Then, after stopping the agitation, a moltenpolymer was taken from the polymer dispenser. After water-cooling themolten polymer, the cooled polymer was pelletarized to obtain a pellet(about 13 kg). Thus obtained polymer had the terminal amino groupconcentration of [NH₂]=33.5 mmol/kg, and the melting point of Tm =174°C.

Example 5

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(15 kg), a polyglycol (4.363 kg) having amino groups at both terminals(Trade name “XTJ-542” manufactured by Suntechno Chemical Co.), andadipic acid (0.637 kg). After the vessel was sufficiently purged withnitrogen, the vessel was gradually heated from a room temperature to235° C. over 3 hours with supplying nitrogen gas at a flow rate of 300L/minute, subsequently the polymerization was conducted for 6 hours withkeeping conditions. Thereafter, hexamethylenediamine (5.0 g) was addedinto the vessel, and polymerization was conducted for another 2 hours.The pressure in the vessel was adjusted to 0.05 MPa after startingheating. Then, after stopping the agitation, a molten polymer was takenfrom the polymer dispenser. After water-cooling the molten polymer, thecooled polymer was pelletarized to obtain a pellet (about 13 kg). Thusobtained polymer had the terminal amino group concentration of [NH₂]=71mmol/kg, and the melting point of Tm =168° C.

Example 6

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(15 kg), a polyethylene glycol (0.8 kg) having amino groups at bothterminals (Trade name “XTJ-504” manufactured by Suntechno Chemical Co.),and adipic acid (0.637 kg). After the vessel was sufficiently purgedwith nitrogen, the vessel was gradually heated from a room temperatureto 235° C. over 3 hours with supplying nitrogen gas at a flow rate of300 L/minute, subsequently the polymerization was conducted for 6 hourswith keeping conditions. Thereafter, hexamethylenediamine (3.5 g) wasadded into the vessel, and polymerization was conducted for another 2hours. The pressure in the vessel was adjusted to 0.05 MPa afterstarting heating. Then, after stopping the agitation, a molten polymerwas taken from the polymer dispenser. After water-cooling the moltenpolymer, the cooled polymer was pelletarized to obtain a pellet (about13 kg). Thus obtained polymer had the terminal amino group concentrationof [NH₂]=58 mmol/kg, and the melting point of Tm =168° C.

Example 7

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(15 kg), a polyethylene glycol (0.8 kg) having amino groups at bothterminals (Trade name “XTJ-504” manufactured by Suntechno Chemical Co.),and adipic acid (0.637 kg). After the vessel was sufficiently purgedwith nitrogen, the vessel was gradually heated from a room temperatureto 235° C. over 3 hours with supplying nitrogen gas at a flow rate of300 L/minute, subsequently the polymerization was conducted for 6 hourswith keeping conditions. Thereafter, maleic anhydride (3.0 g) was addedinto the vessel, and polymerization was conducted for another 2 hours.The pressure in the vessel was adjusted to 0.05 MPa after startingheating. Then, after stopping the agitation, a molten polymer was takenfrom the polymer dispenser. After water-cooling the molten polymer, thecooled polymer was pelletarized to obtain a pellet (about 13 kg). Thusobtained polymer had the terminal amino group concentration of [NH₂]=1mmol/kg, and the melting point of Tm =168° C.

Example 8

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(8 kg), a polyglycol (10.47 kg) having amino groups at both terminals(Trade name “XTJ-542” manufactured by Suntechno Chemical Co.), andadipic acid (1.53 kg). After the vessel was sufficiently purged withnitrogen, the vessel was gradually heated from a room temperature to235° C. over 3 hours with supplying nitrogen gas at a flow rate of 300L/minute, subsequently the polymerization was conducted for 8 hours withkeeping conditions. The pressure in the vessel was adjusted to 0.05 MPaafter starting heating. Then, after stopping the agitation, a moltenpolymer was taken from the polymer dispenser. After water-cooling themolten polymer, the cooled polymer was pelletarized to obtain a pellet(about 11 kg). Thus obtained polymer had the terminal amino groupconcentration of [NH₂]=18.6 mmol/kg, and the melting point of Tm =134°C.

Example 9

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(15 kg), a polypropylene glycol (8 kg) having amino groups at bothterminals (Trade name “D-2000” manufactured by Suntechno Chemical Co.),and adipic acid (0.6 kg). After the vessel was sufficiently purged withnitrogen, the vessel was gradually heated from a room temperature to235° C. over 3 hours with supplying nitrogen gas at a flow rate of 300L/minute, subsequently the polymerization was conducted for 7 hours withkeeping conditions. The pressure in the vessel was adjusted to 0.05 MPaafter starting heating. Then, after stopping the agitation, a moltenpolymer was taken from the polymer dispenser. After water-cooling themolten polymer, the cooled polymer was pelletarized to obtain a pellet(about 21 kg). Thus obtained polymer had the terminal amino groupconcentration of [NH₂]=31 mmol/kg, and the melting point of Tm =161° C.

Comparative Example 1

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(15 kg), a polyethylene glycol (0.8 kg) having hydroxyl groups at bothterminals and having a number average molecular weight of about 150, andadipic acid (0.637 kg). After the vessel was sufficiently purged withnitrogen, the vessel was gradually heated from a room temperature to235° C. over 3 hours with supplying nitrogen gas at a flow rate of 300L/minute, subsequently the polymerization was conducted for 7 hours withkeeping conditions. The pressure in the vessel was adjusted to 0.05 MPaafter starting heating. Then, after stopping the agitation, a moltenpolymer was taken from the polymer dispenser. After water-cooling themolten polymer, the cooled polymer was pelletarized to obtain a pellet(about 13 kg). Thus obtained polymer had the terminal amino groupconcentration of [NH₂]=3 mmol/kg, and the melting point of Tm =168° C.

Comparative Example 2

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(15 kg), a polypropylene glycol (1.5 kg) having hydroxyl groups at bothterminals and having a number average molecular weight of about 200, apolytetramethylene glycol (2.8 kg) having hydroxyl groups at bothterminals and having a number average molecular weight of about 650, andadipic acid (0.637 kg). After the vessel was sufficiently purged withnitrogen, the vessel was gradually heated from a room temperature to235° C. over 3 hours with supplying nitrogen gas at a flow rate of 300L/minute, subsequently the polymerization was conducted for 7 hours withkeeping conditions. The pressure in the vessel was adjusted to 0.05 MPaafter starting heating. Then, after stopping the agitation, a moltenpolymer was taken from the polymer dispenser. After water-cooling themolten polymer, the cooled polymer was pelletarized to obtain a pellet(about 13 kg). Thus obtained polymer had the terminal amino groupconcentration of [NH₂]=2 mmol/kg, and the melting point of Tm =165° C.

Comparative Example 3

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(11.2 kg), a polyethylene glycol (1.15 kg) having hydroxyl groups atboth terminals and having a number average molecular weight of about150, and adipic acid (1.12 kg). After the vessel was sufficiently purgedwith nitrogen, the vessel was gradually heated from a room temperatureto 235° C. over 3 hours with supplying nitrogen gas at a flow rate of300 L/minute, subsequently the polymerization was conducted for 7 hourswith keeping conditions. The pressure in the vessel was adjusted to 0.05MPa after starting heating. Then, after stopping the agitation, a moltenpolymer was taken from the polymer dispenser. After water-cooling themolten polymer, the cooled polymer was pelletarized to obtain a pellet(about 11 kg). Thus obtained polymer had the terminal amino groupconcentration of [NH₂]=3 mmol/kg, and the melting point of Tm =168° C.

Comparative Example 4

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(17 kg), a polypropylene glycol (1.1 kg) having hydroxyl groups at bothterminals and having a number average molecular weight of about 200, apolytetramethylene glycol (1.67 kg) having hydroxyl groups at bothterminals and having a number average molecular weight of about 650, andadipic acid (0.38 kg). After the vessel was sufficiently purged withnitrogen, the vessel was gradually heated from a room temperature to235° C. over 3 hours with supplying nitrogen gas at a flow rate of 300L/minute, subsequently the polymerization was conducted for 7 hours withkeeping conditions. The pressure in the vessel was adjusted to 0.05 MPaafter starting heating. Then, after stopping the agitation, a moltenpolymer was taken from the polymer dispenser. After water-cooling themolten polymer, the cooled polymer was pelletarized to obtain a pellet(about 13 kg). Thus obtained polymer had the terminal amino groupconcentration of [NH₂]=2 mmol/kg, and the melting point of Tm =174° C.

Comparative Example 5

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(15 kg), a polypropylene glycol (1.5 kg) having hydroxyl groups at bothterminals and having a number average molecular weight of about 200, apolytetramethylene glycol (2.8 kg) having hydroxyl groups at bothterminals and having a number average molecular weight of about 650 andadipic acid (0.637 kg). After the vessel was sufficiently purged withnitrogen, the vessel was gradually heated from a room temperature to235° C. over 3 hours with supplying nitrogen gas at a flow rate of 300L/minute, subsequently the polymerization was conducted for 6 hours withkeeping conditions. Thereafter, hexamethylenediamine (10.0 g) was addedinto the vessel, and polymerization was conducted for another 2 hours.The pressure in the vessel was adjusted to 0.05 MPa after startingheating. Then, after stopping the agitation, a molten polymer was takenfrom the polymer dispenser. After water-cooling the molten polymer, thecooled polymer was pelletarized to obtain a pellet (about 13 kg). Thusobtained polymer had the terminal amino group concentration of [NH₂]=71mmol/kg, and the melting point of Tm =168° C.

Comparative Example 6

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(15 kg), a polyethylene glycol (0.8 kg) having hydroxyl groups at bothterminals and having a number average molecular weight of about 150, andadipic acid (0.637 kg). After the vessel was sufficiently purged withnitrogen, the vessel was gradually heated from a room temperature to235° C. over 3 hours with supplying nitrogen gas at a flow rate of 300L/minute, subsequently the polymerization was conducted for 6 hours withkeeping conditions. Thereafter, hexamethylenediamine (7.0 g) was addedinto the vessel, and polymerization was conducted for another 2 hours.The pressure in the vessel was adjusted to 0.05 MPa after startingheating. Then, after stopping the agitation, a molten polymer was takenfrom the polymer dispenser. After water-cooling the molten polymer, thecooled polymer was pelletarized to obtain a pellet (about 13 kg). Thusobtained polymer had the terminal amino group concentration of [NH₂]=58mmol/kg, and the melting point of Tm =168° C.

Comparative Example 7

Into a pressure vessel (70 L) equipped with an agitator, a thermometer,a torque meter, a manometer, an nitrogen gas inlet, a pressureregulator, and a polymer dispenser, were charged 12-aminododecanoic acid(8 kg), a polypropylene glycol (4.1 kg) having hydroxyl groups at bothterminals and having a number average molecular weight of about 200, apolytetramethylene glycol (6.7 kg) having hydroxyl groups at bothterminals and having a number average molecular weight of about 650 andadipic acid (1.53 kg). After the vessel was sufficiently purged withnitrogen, the vessel was gradually heated from a room temperature to235° C. over 3 hours with supplying nitrogen gas at a flow rate of 300L/minute, subsequently the polymerization was conducted for 8 hours withkeeping conditions. The pressure in the vessel was adjusted to 0.05 MPaafter starting heating. Then, after stopping the agitation, a moltenpolymer was taken from the polymer dispenser. After water-cooling themolten polymer, the cooled polymer was pelletarized to obtain a pellet(about 11 kg). Thus obtained polymer had the terminal amino groupconcentration of [NH₂]=1 mmol/kg, and the melting point of Tm =134° C.

The results are shown in Table 1.

TABLE 1 Bonded strength (N/cm) [NH₂] T_(m) T_(m) + T_(m) − No. (mmol/kg)(° C.) TPU 10(° C.) T_(m)(° C.) 10(° C.) Ex. 1 31 168 TPU-01 65 54 38TPU-02 68 55 35 Ex. 2 37 165 TPU-01 71 57 31 TPU-02 68 61 30 Ex. 3 23168 TPU-01 61 45 29 TPU-02 62 48 31 Ex. 4 33.5 174 TPU-01 52 34 28TPU-02 45 32 27 Ex. 5 71 168 TPU-01 83 66 45 TPU-02 79 70 48 Ex. 6 58168 TPU-01 45 35 20 TPU-02 58 50 31 Ex. 7 1 168 TPU-01 40 30 21 TPU-0239 29 20 Ex. 8 18.6 134 TPU-01 48 37 25 TPU-02 45 33 26 Ex. 9 31 161TPU-01 57 40 27 TPU-02 48 39 27 Com. 3 168 TPU-01 40 25 5 Ex. 1 TPU-0241 24 3 Com. 2 165 TPU-01 22 7 2 Ex. 2 TPU-02 18 5 1 Com. 3 168 TPU-0140 28 15 Ex. 3 TPU-02 46 30 18 Com. 2 174 TPU-01 19 5 1 Ex. 4 TPU-02 206 3 Com. 71 168 TPU-01 40 32 19 Ex. 5 TPU-02 39 29 18 Com. 58 168 TPU-0139 35 20 Ex. 6 TPU-02 38 36 21 Com. 1 134 TPU-01 10 5 1 Ex. 7 TPU-02 113 1

1. A molded composite article which comprises (Ia) a resin membercomprising a polyamide resin and (IIa) a resin member which is directlybonded to the resin member (Ia) and comprises a thermoplasticpolyurethane resin, wherein the polyamide resin comprises a polyamideblock copolymer containing (A) a polyether segment having at least oneterminal —NH— group, and the thermoplastic polyurethane resin comprisesa polyester polyurethane obtained from a polyester diol.
 2. A moldedcomposite article according to claim 1, wherein the polyamide blockcopolymer comprises a polyamide elastomer.
 3. A molded composite articleaccording to claim 1, wherein the polyether segment (A) is a polyethersegment which is a condensate of a polyhydric alcohol having 2 to 8carbon atoms, and has at least one terminal —NH— group.
 4. A moldedcomposite article according to claim 3, wherein the polyhydric alcoholis a straight or branched chain aliphatic polyhydric alcohol having 2 to4 carbon atoms.
 5. A molded composite article according to claim 3,wherein the polyhydric alcohol is a straight or branched chain aliphaticpolyhydric alcohol having 2 to 3 carbon atoms.
 6. A molded compositearticle according to claim 1, wherein the polyether segment (A) has abranched chain having a free amino group.
 7. A molded composite articleaccording to claim 1, wherein the proportion of the polyether segment(A) is 10 to 90% by weight in the polyamide block copolymer.
 8. A moldedcomposite article according to claim 1, wherein the polyamide resin hasa free amino group in a concentration of not less than 10 mmol/kg.
 9. Amolded composite article according to claim 8, wherein the polyamideresin is a resin composition which comprises the polyamide blockcopolymer containing the polyether segment (A).
 10. A molded compositearticle according to claim 9, wherein the polyamide resin is a resincomposition which comprises both the polyamide block copolymercontaining the polyether segment (A) and (C) a compound having a freeamino group, wherein the compound (C) having a free amino group is atleast one member selected from the group consisting of a monoamine, apolyamine, a polyamide oligomer and a polyamide resin which is not thepolyamide block copolymer.
 11. A molded composite article according toclaim 10, wherein the proportion of the compound (C) having a free aminogroup is 0.01 to 20% by weight in the total resin composition.
 12. Amolded composite article according to claim 1, wherein the thermoplasticpolyurethane resin comprises a thermoplastic polyurethane elastomer. 13.A molded composite article according to claim 1, wherein thethermoplastic polyurethane resin comprises, a polyester ether urethaneelastomer, and a polycarbonate urethane elastomer.
 14. A shoe or a rollcomprising the molded composite article according to claim
 1. 15. Aprocess for producing a molded composite article recited in claim 1,which comprises heating at least one selected from the group consistingof (i) the resin member (Ia) and (ii) the resin member (IIa) to bond theresin member (Ia) to the resin member (IIa).
 16. A production processaccording to claim 15, which comprises heating the thermoplasticpolyurethane resin until molten, bringing the molten thermoplasticpolyurethane resin into contact with at least part of a resin membercomprising the polyamide resin to bond the thermoplastic polyurethaneresin to the polyamide resin member.
 17. A process according to. claim15, which comprises heating the polyamide resin until molten, bringingthe molten polyamide resin into contact with at least part of a resinmember comprising the thermoplastic polyurethane resin to bond thepolyamide resin to the thermoplastic polyurethane resin member.
 18. Aprocess according to claim 15, which comprises heating both of thepolyamide resin and the thermoplastic polyurethane resin until molten,bringing the molten polyamide resin into contact with the moltenthermoplastic polyurethane resin to bond both resins together.
 19. Aprocess according to claim 15, wherein the polyamide resin and thethermoplastic polyurethane resin are bonded together in the moldingprocess by a molding method selected from the group consisting of a heatpress molding, a vacuum molding, an injection molding, an extrusionmolding, and a blow molding.